96 



CRUvSTACEA MALACOSTRACA. II. 



Thoracic segments siibrectangular (fig. 4a) with their lateral margins slightly convex; third 

 segment conspicnonsly less than half as long again as the second. — Legs of middle length (figs. 4 b 

 and 4c), and seventh joint with claw a little longer than sixth joint. Second and third pairs with 

 sixth joint abont as long as fifth plus half of the fourth and the settc somewhat short; three posterior 

 pairs (fig. 4c^ with some of the set£e rather long. 



Abdomen deep (fig. 4d) and as long as the sum of the three posterior thoracic segments; the 

 ventral serration is low and feebly developed, but the margin of each segment shows a sharp angle. 

 Pleopods small, but both rami with some well developed setse about as long as the rami (fig. 4e). 

 Sixth segment, seen from above (fig. 4 a), as long as the sum of the three preceding segments and 

 posteriorly broadly rounded. — Uropods (figs. 4d and 4e) only about half as long as their segment; 

 peduncle deep; endopod with first joint almost as deep as long, thicker and much shorter than second 

 joint and as long as, or slightly shorter than, the thin exopod. 



Length of the largest specimen, a female without marsupium, 1.9™'". 



Remarks. L. crassa is similar to L. brcvireiiiis, but differs in several particulars. The an- 

 tennulse have the two proximal joints conspicuously thicker, but the fourth joint slender and cylindrical 

 instead of conical. The chelipeds are much more robust with the carpus considerably deeper, the hand 

 shorter in proportion to the movable finger than in A. brcvireiiiis and two strong setae instead of one 

 at the posterior base of the fixed finger. The abdomen has the ventral serration much less developed 

 and the pleopods and uropods are distinctly smaller than in the other species. 



Occurrence. Taken by the "Ingolf at its deepest station. 



South of Davis Strait: St. 38: Lat. 59°i2' N., Long. 51° 05' W., 1870 fm., temp. 1.3°; 6 spec. 



It may be added that after I had discovered the six specimens of this species between the 

 specimens of L. brevircmis from the same station, I looked in vain for more specimens among the 

 numerous specimens of the last-named species from the other fourteen "Ingolf stations. 



Group c, subdivision ;- (Vid. p. 85). 



61. Leptognathia polita n. sp. 

 (PI. IX, figs. 5a-5f.) 



Female (without marsupium). Moderately robust (fig. 5a), about .six and a half times as long 

 as broad and seen from above subcylindrical, yet with the carapace and the middle of 'abdomen slightly 

 broader than the thoracic segments, which have their lateral margins almost straight, being curved 

 only at both ends of each segment. — Carapace slightly longer than the sum of the two next seg- 

 ments, seen from above (fig. 5a) nearly hexagonal and broadest considerabh- before the middle, where 

 each lateral margin has a pronounced angle, and from these angles the margins converge slightly to 

 the base and strongly to the front end, which is conspicuou.sly less than half as broad as the carapace 

 between the angles mentioned; frontal process low, rounded. 



Antennulse (fig. 5b) much shorter than the carapace and rather slender. First joint almost as 

 long as the other joints combined, two and a half times as long as deep; second joint considerably 

 produced above, half as long as the first and above a little more than twice as long as deep; third 



